Socket structure



2 Sheets-Sheet 1 INVENTOR J. P. MORONE, JR

SOCKET STRUCTURE Nov. 11, 1958 Filed March 26, 1956 Nov. 11, 1958 J. P. MORONE, JR

SOCKET STRUCTURE 2 Sheets-Sheet 2 Filed March 26, 1956 United States Patent SOCKET STRUCTURE Joseph P. Moi-one, Jr., Indianapolis, Ind., assignor to P. R. Mallory & Co., Inc., Indianapolis, Ind, a corporation of Delaware This invention relates to socket structures for use with devices having contact prongs, and, more particularly, to tube sockets for electron tubes of small dimensions, such as for so-called subminiature tubes.

One common form of conventional tube socket com-' prised a socket body of molded insulating material having a plurality of prong-receiving bores formed therein, corresponding in number to that of the contact prongs or pins of the tube. A contact member generally formed of spring metal was held in each of said bores and was so constructed and arranged as to frictionally grip the prong or pin of the tube, thereby not only providing electrical connection of low resistance between the prong and the contact member, but also holding the tube against accidental displacement.

While conventional tube sockets of the described general type have been satisfactory for standard size tubes, they had serious deficiencies when it Was attempted to adapt their structural organization for miniature and subminiature tubes. In that case, it was necessary to proportionately reduce the dimensions of all socket components, making it impossible to accommodate contact members or springs having sufficient compliance to assure good electrical contact. Therefore, commercially available tube sockets for subminiature tubes had several recognized deficiencies, the principal ones being high and erratic contact resistance and poor tube retention characteristics. Although various suggestions and proposals were made to provide a satisfactory tube socket for subminiature tubes, none of these suggestions and proposals was completely satisfactory and successful on a practical and industrial scale.

It has been discovered that the outstanding problem may be solved in a remarkably simple manner.

It is an object of the present invention to improve tube sockets for electron tubes of small dimensions, such as for subminiature tubes.

It is another object of the prseent invention to provide a novel right-angle tube socket, particularly suitable for button-base and flat-press subminiature tubes in printed circuit applications, having improved electrical and mechanical characteristics.

It is a further object of the invention to provide a novel and improved tube socket for button-base and flat-press subminiature tubes which is simple in structure, has low contact resistance and good tube retention characteristics, and which may be readily manufactured on a quantity production scale at a low cost.

Other and further objects and advantages of the pres- Q ent invention will become apparent from the following description, taken in conjunction with the accompanying drawings, in which:

Fig. 1 is a front elevational view of a right-angle tube socket for eight-pin, button-base subminiature tubes embodying the principles of the present invention;

Fig. 2 is a side elevational view of the socket shown in Fig. 1;

Fig. 3 is a section taken on line 3-3 of Fig. 1;

Fig. 4 is a section taken on line 44 of Fig. 1;

Fig. 5 is a section taken on line 55 of Fig. 1;

Fig. 6 is a section taken on line 6-6 of Fig. 1;

Fig. 7 is a front elevational view of a right-angle tube socket for flat-press subminiature tubes embodying the principles of the invention;

Fig. 8 is a side elevational view of the socket shown in Fig. 7;

Fig. 9 is a section taken on line 9--9 of Fig. 7;

Fig. 10 is a section taken on line 1(l10 of Fig. 7; and

Fig. 11 is a section taken on line 11-11 of Fig. 7, and shows the tube socket of the invention with one of the tube prongs inserted therein.

In the drawings, all dimensions are shown on a greatly enlarged scale for the sake of clarity of illustration.

Referring now more particularly to Figs. 1 to 6 of the drawings, reference numeral 12 denotes a socket body integrally formed or molded from insulating material. A plurality of bores or cavities 14 of rectangular crosssection' arranged in a circle are provided in said socket body and extend from one end face 15 of the body to the other end face 16 of the body. A plurality of integrally formed rectangular projections 17, equal in number to that of cavities 14, extend from the bottom face 18 of socket body 12. The object of these projections is to space the socket from a chassis or panel upon which the socket is mounted, thereby to permit the evaporation of any condensate between the two, thus making the structure free of moisture traps. In addition, the said projections also serve for securing an integral extension or lug of the contact member thereto, as it will be set forth more fully hereinafter. The end of each cavity terminates in depressed portions 19 and 20 in the respective en'd faces 15 and 16 of the socket body, defining ledges 21a, 21b and 22a, 22b, respectively. 1

In each cavity there is provided a contact member in tegrally formed of metal of high electrical conductivity, such as copper, generally denoted by numeral 23. This member comprises an ear 24 bent down against ledge 22a of the socket body, a prong-engaging portion 25 lining an inside face of rectangular cavity 14 and a terminal portion 26 following ledge 21a of the said body and continued downwardly beyond the said body. The said terminal portion is of such length that it can extend through an aperture provided in a printed circuit panel so that soldered electrical connections may be made thereto both above and below the panel, if desired. An in tegral lug 27 extends from the terminal portion and is bent around a corresponding bottom projection 17 of the socket body. Thus, the contact member is securely held in the cavity by the combined action of bent down ear 24 and lug 27.

A spring member 28 is provided in each of cavities 14, opposite to the prong-engaging portion of the contact member 23. The spring member is integrally formed of a strip of spring metal having a bowed or arched center portion ending in cars 29, respectively engaging ledges 21b and 22b of the socket body. In assembling the socket, first the contact memberis slipped through the cavity and is then permanently secured to the socket body by bending lug 27 of the said member obtained through use of a metal bracket 3t? which fits over the socket body. This bracket is placed over the body in mounting the socket on a chassis or panel. Lugs 31 of the bracket are passed through properly spaced apertures in the panel and are then formed over, hold ing the .socket securely in place. Lateral displacement of the socket body is prevented by ledges 32 formed on the socket body which are in engagement with the correspondingly cut-out :side edges of bracket 1310. The top portionof .the bracket is also provided with a lateral extension 33' secured :to the socket body by means of a rivet or eyelet 34 extending through an aperture 55 in tlhe said body arranged centrally with respect to cavities As it will be best observed .in .Fig. l, in assembling the tube socket of the invention shown in Figs. 1''6, contact members having four 'difi'erent'configurations are provided, two of each being used to build up a complete eight-pin socket. 'It is further to be noted that the terminal portions of adjoining contact members are so arranged as to extend along opposite end faces of the socket body in order to provide increased spacing between the terminal portions :at the same side of the said body.

.From the foregoing description, the operation of the tube socket of the invention will be readily understood by those skilled in the art. When it is desired to insert a button type subminiature tube into the socket, the relatively flexible leads or prongs protruding from the glass base of the tube and cut to a predetermined length are introduced into the cavities of the socket. The leads or prongs of the tube will slide between the contact and spring members of each cavity and the prongs will be pressed against the prong-engaging portion of the con tact member with appreciable force, thereby assuring good contact and tube retention characteristics.

The two-piece spring-contact assembly just described, which is one of the important features of the present invention, provides the advantage of superior spring performance, Without sacrificing good electrical performance. The contact member of the assembly has no spring function and thus may be of a highly conductive material, such as copper or silver, the electrical performance of which is not appreciably affected over wide temperature ranges. The spring member, on the other hand, has no electrical function and therefore may be of spring material, such as beryllium copper, or even steel, the electrical characteristics of which are only of minor importance. The snap-in arrangement of the spring members permits the use of superior materials that do not lend themselves to forming, staking, or bending operations, which would otherwise be required to retain them in the cavity. The spring structure of the invention also permits the substitution of high quality materials'for the r conventional copper-base spring alloys where high temperature operation is desired.

Figs. 7-11 show a modified embodiment of the present invention into a right-angle tube socket for flat-press subminiature tubes. Apart from the fact that the prongreceiving cavities are located in one line, rather than arranged in a circle, the structure of this tube socket is closely similar to the one described in connection with Figs. 1-6 of the drawing and similar reference numerals have been used to denote corresponding parts. Reference numeral 42 denotes a socket body integrally formed or molded from insulating material. A plurality of bores or cavities 44 of rectangular cross-section arranged in a straight line are provided in said socket body and extend from one end face 45 of the body to the other end face 46 of the body. A plurality of integrally formed rectangular projections 47, equal in number to that of cavities 44, extend from the bottomface 48 of socket body 42. These projections, in addition to spacing the socket body from the mounting panel, serve for securing an integral extension of the contact member thereto. The end of each cavity terminates in depressed portions 49 and 50 in the respective end faces 45 and 46 of the socket body, defining ledges 51a, 51b and 52a, 52b, respectively.

In. each cavity, there is provided a contact member 53 of high conductivity metal comprising an ear 5 4 bent down against ledge 52a of the socket body, a prongengaging portion 55 lining an inside face of rectangular cavity 44, and a terminal portion 56 following ledge 51a of the said body and continued downwardly beyond the said body. An integral lug 57 extends from the terminal portion and is bent around a corresponding bottom projection 47 of the socket body, whereby the contact member is secured in the cavity by the combined action of bent-down ear 54 and lug 57.

A spring member 58 is provided in each of cavities 44, opposite to prong-engaging portion of the contact member 53. The spring member is integrally formed of a strip of spring metal having an arched center portion ending in cars 59, respectively engaging ledges 51b and 52b of the socket body. The contact member and the spring member are assembled with the socket body in the same manner as has been described in connection with the socket shown in Figs. 1-6. It will be noted that the contact members are all of the same shape and that contact members in adjoining cavities are so inserted as to have their terminal portions extend along opposite end faces of the socket body, thereby increasingthe spacing between the terminal portions on the same end face of the said body.

The socket is secured to a panel by means of a metal bracket 60 which fits over the socket body, the said bracket having integrally formed lugs 61 which may be passed through suitably spaced apertures of the panel and bent over to hold the socket in place.

In view of the close s'milarity of the construction of the tube socket just described with that of Figs 1-6, its

operation will be readily understood without any detailed:

explanation. As shown in Fig. 11, upon insertion of a fiat-press subminiature tube into the socket, each tube pin or prong 62 will be frictionally gripped andsecurely held between prong-engaging portion 55 of contact member 53 and the compressed and resiliently stressed arched portion of spring member 58. It will be noted that the ear of the spring member nearest the base of'the tube remains in contact with ledge 5212 which it engages prior to prong insertion, while the other ear of the said spring member moves away from ledge 51b which it engages prior to prong insertion.

Although the present invention has been described in connection with a few preferred embodiments thereof,

in a circle and extending from one end face of said body to the other end face of said body, a plurality of spaced projections on the bottom of said socket body for spacing said body from a chassis upon which the socket is mounted with its cavities in parallelism with the plane of said chassis, an elongated metal contact member formed of metal of high electrical conductivity for each cavity comprising a prong-engaging portion within the cavity and lining a face thereof and a terminal portion outside of the cavity extending along and beyond one end face of the socket body, said contact member being secured to said socket body by means of an car at one end of the cavity and by an integral lug bent around one of said bottom projections of said socket body, an arched spring member formed of springmetal of lower electrical conductivity in each cavity having an car at each end in engagement with the respective end faces of thesocket body, the arched portion of said spring member being normally biased against the prong-engaging portion of said contact member and being adapted to maintain a contact prong inserted in said cavity in pressure contact with said prong-engaging portion, said contact member having no spring function and said spring member having no contact function during operation of the tube socket.

2. In a right angle tube socket for fiat-press subminiature tubes, the combination which comprises a generally rectangular socket body of insulating material having a plurality of rectangular prong-receiving cavities arranged in one line and extending from one end face of said body to the other end face of said body, a plurality of spaced projections on the bottom of said socket body for spacing said body from a chassis upon which the socket is mounted with its cavities in parallelism with the plane of said chassis, an elongated metal contact member formed of metal of high electrical conductivity for each cavity comprising a prong-engaging portion within the cavity lining a face thereof and a terminal portion outside of the cavity 7 extending along and beyond one end face of the socket jections of said socket body, and an arched spring member formed of spring metal of lower electrical conductivity in each cavity having an car at each end in engagement with the respective end faces of the socket body, the arched portion of said spring member being normally biased against the prong-engaging portion of said contact member and being adapted to maintain a contact prong inserted in said cavity in pressure contact with said prongengaging portion, said contact member having no spring function and said spring member having no contact function during operation of the tube socket.

References Cited in the file of this patent UNITED STATES PATENTS 1,536,149 Schmid May 5, 1925 2,188,789 Kimball Jan. 30, 1940 2,301,447 Parker Nov. 10, 1942 2,606,228 Chouljian Aug. 5, 1952 2,613,244 Del Camp Oct. 7, 1952 FOREIGN PATENTS 359,130 Italy May 13, 1938 428,579 Italy Dec. 22, 1947 

